“The first time I saw a 73-page ‘book’ offered on Amazon, I was outraged,” says New York Times best selling author Michael Levin. “But I thought about how shredded the American attention span is. And I felt like Cortez staring at the Pacific.”

The trend in books today, Harry Potter notwithstanding, is toward books so short that in the past no self-respecting publisher—or author—would even have called them books. But today, shortened attention spans call for shorter books.

Levin blames smartphones and social media for what he calls “a worldwide adult epidemic of ADH…ooh, shiny!”

“Brain scientists tell us our brain chemistry has been transformed by short-burst communication such as texting, Tweeting, and Facebook posts,” Levin adds. “Long magazine articles have given way to 600-word blog posts. And doorstop-size books have been replaced by minibooks.”

This sudden change in attention spans changed the way Levin approaches ghostwriting. “Even five years ago, we aimed for 250-page books. Today we advise our business clients to do 50-page minibooks to meet impatient readers’ expectations for speedy delivery of information.”

Levin, who runs the ghostwriting firm BusinessGhost.com and was featured on ABC’s Shark Tank, says that people are looking for leadership disguised as a book. “Today,” he asserts, “people don’t want you to prove your assertions. They just want to know that you have legitimate answers to their questions and that they can trust you. If you can’t get buy-in with 50 pages today, you won’t get it in 250.”

The trend toward shorter books caused Levin to offer what he calls the “Book-Of-The-Quarter Club,” which creates four 50-page hardcover minibooks a year for BusinessGhost’s clients. “This allows them to address four different major issues, or four different sets of prospects, and provides quarterly opportunities for marketing events,” Levin says.

Michael Levin, founder and CEO of BusinessGhost, Inc., has written more than 100 books, including eight national best-sellers; five that have been optioned for film or TV by Steven Soderbergh/Paramount, HBO, Disney, ABC, and others; and one that became “Model Behavior,” an ABC Sunday night Disney movie of the week. His new minibook, “The Financial Advisor's Dilemma,” teaches how to create trust and distinctiveness in the highly competitive marketplace.